adapt_framework: incorrect device classes with adapt-contrib-languagePicker

[danielghost]

Subject of the issue/enhancement/features

If using https://github.com/adaptlearning/adapt-contrib-languagePicker, it is possible for the size and orientation classes to be incorrect on the html tag once the course has fully loaded/initialized.

Your environment

• adapt_framework 5.12.1, but not specific to this version

Steps to reproduce

• Ensure adapt-contrib-languagePicker is installed and enabled, with "_showOnCourseLoad": true
• Before selecting a language, resize the browser enough to enter a different breakpoint, i.e. large to small, portrait to landscape
• Pick a language and then inspect the html classes which will still be set to the original values when the course loaded

Expected behaviour

https://github.com/adaptlearning/adapt_framework/blob/master/src/core/js/device.js doesn't listen to resize orientationchange events until Adapt#app:dataReady, which occurs after the languagePicker, so any changes made before a language selection are redundant and not reflected in the html classes once the data is ready.

Proposed change

The most obvious solution would be to change https://github.com/adaptlearning/adapt_framework/blob/master/src/core/js/device.js#L19 to listen to configModel:dataLoaded or offlineStorage:ready.